Subaru Conversion Won't Idle Options

[turnaround89]

Hi everyone, so December 2018 was the first time I got to hear the WRX STi motor I purchased run. It ran rough because the intake wasn't connected, hardly any sensors hooked up, etc. However, it ran and that made me happy knowing my investment wasn't useless.

The engine that was purchased is supposed to be a subaru wrx gc8 sti v4 turbo ej20

Cut to a few months later, now I have all the required sensors (MAF, purge solenoid, ignitor, etc) that I was missing purchased and hooked up. Vacuum hoses hooked up and I thought now the engine should run and idle beautifully. Nope, it will fire and run for maybe 3 seconds then shut off. Check out the video in the link.

Subaru Engine Video

The only thing I dont have hooked up are to the non-pressure side of the intake. I tried plugging these holes today and the car did t idle any better. Now, I need to find a permanent solution to these holes, but I swear the engine is running worse now with everything hooked up then in December with nothing hooked up.

Any ideas where I could start?

I was thinking fuel pressure and timing would be my next step. In the video you can hear the fuel pump prime the system before the engine kicks over.

The wiring harness was sent out to iwire services to be redone and that appears to be functioning properly.

Thank you everyone for your help.

[lierofox]

Mine's the exact same EJ20K engine for my swap, I went with a front-cut and in my case it came with a blow-off valve and the original recirculation valve port was capped off, but yes, in stock configuration the recirculation valve goes from the intercooler to the turbo inlet tube that runs under the intake manifold, between the turbo and the MAF (though at idle the presence of a blow-off valve or recirculation valve shouldn't matter as long as there's no vacuum leaks either way.)

Do you have both the MAF and the MAP/Boost/Barometric Pressure Sensor hooked up? These engines use both.

Otherwise I'd check the fuel pressure while cranking/running (Those engines will start on basically fumes but won't run well after starting.) Check the intake for any vacuum leaks.

Let's see what else... I've never gotten my EJ20K swap running 100% (particularly when it rains) but I'd double check to make sure your sensors are getting proper power, ground, and signal levels, I know on my MAP sensor the ground wire went down to a junction connector that bridges all the sensor grounds together, but for the MAP sensor it wasn't making any contact, so the voltage divider wasn't able to work properly and the sensor was spitting out a constant +5v down the signal line making the ECU think the car was constantly running at ~30psi of boost.


EDIT: Waaaaaaaaaaaait a tick. I was watching the video a bit closer admiring how good it looks with the intake manifold flipped around and I think I see the problem. Your Idle Air Control valve looks like it's just pulling in through a small filter to the top left, and not plugged into the turbo inlet tube. If so it's not drawing in any air through the MAF sensor at the bottom right of the video at all, so the MAF doesn't think there's any air flowing into the engine, that's all unmetered air that'll bypass the throttle and so the ECU gives it basically zero fuel to keep it running.

(IMG:http://www.914world.com/bbs2/uploads_offsite/i.imgur.com-18880-1556610543.1.png)

Digging through some of my pictures from when I did the timing belt and head gasket on my engine it looks like you're using a turbo inlet from a different engine as well. I don't actually see the port that the idle air valve normally plugs into, which should be right where the turbo inlet tube turns 90 degrees and goes under the intake:

(IMG:http://www.914world.com/bbs2/uploads_offsite/i.imgur.com-18880-1556612318.1.jpg)


It's not the best picture of it, but it's all I could find of the engine as it was in the front-clip before I removed it for the swap, you can see the path the IAC tube normally takes over the inlet to the turbo inlet tube:

(IMG:http://www.914world.com/bbs2/uploads_offsite/i.imgur.com-18880-1556612319.2.jpg)